Aging Impacts Progenitor Cells in the Thymus

The age-related decline of the immune system has several causes, but the involution of the thymus is an important one. The thymus is responsible for the production of mature T cells of the adaptive immune system, but the organ atrophies with age. The supply of new T cells falls off dramatically in later life, and without these reinforcements, the adaptive immune system becomes ever more populated with broken, misconfigured, senescent, exhausted, and outright harmful T cells. A few research groups and companies are investigating ways to restore the thymus, typically by provoking it to regrow. A number of approaches have been demonstrated to accomplish this goal in mammals, with varying degrees of success and reliability. Only two have been shown to work in humans, the growth hormone approach of Intervene Immune, and sex steroid ablation, as used in prostate cancer and hematopoietic stem cell transplant patients. Today's open access paper provides confirming evidence for the atrophy of the thymus to be a function of changes in the progenitor cells of the thymic epithelium, responsible for providing daughter somatic cells to populate this tissue. If stem cells and progenitor cells become dysfunctional, a slow atrophy of the surrounding tissues is more or less exactly what one would expect. This is seen in the loss of muscle mass and strength with aging, for example, relating to the declining activity of muscle stem cells. This work is interesting in the context of ...
Source: Fight Aging! - Category: Research Authors: Tags: Medicine, Biotech, Research Source Type: blogs